地下室墙和地板绝缘，水管理
I’ve spent hours reading through many of the Q&A questions regarding basement insulation and water issues and they have been extremely helpful. My house is located in St. Paul, Minnesota, was built in the 40’s and the basement has had bulk water infiltration through walls and window wells and seepage through the concrete block, resulting in the usual wetness and mold problems. The exterior is brick and in a 20’ section along the front of the house approximately 5 courses were below grade. In one rain storm water seeped through the brick, down the main floor wall and dripped through the drywall ceiling in one of the finished bedrooms. Because of this and previous water issues we excavated down to the footings last fall on approximately 2/3 of the exterior, cleaned and waterproofed the block and below grade brick (masterseal HLM 5000), applied 2” or rigid foam below grade and added exterior drain tile that was tied in to an existing sump pump. The basement has been gutted (lots of rotten and molded wood) and water seepage/droplets through the concrete block can be seen on the exterior walls next to the slab for the garage and sunroom – these walls have no exterior waterproofing. There is currently interior drain tile around most of the basement. The basement will be insulated and finished but I’m not sure how best to address the current water problems. My initial thought is to remove the perimeter concrete, apply a dimpled membrane against the walls that are currently seeping (or all walls??), lap the membrane onto the drain tile and install new concrete. Rigid foam would then be installed against the membrane (air sealed with high quality tape and foam/caulk) and the top would be sealed with spray foam that would also seal the rim joists. Some of the other Q&A’s specifically say do not install a polyethylene vapor barrier anywhere (//m.etiketa4.com/blogs/dept/musings/how-insulate-basement-wall). Isn’t this exactly what the dimpled membrane would be, equivalent to a polyethylene vapor barrier? If a dimpled membrane is advised should it only be placed on the areas that do not have exterior waterproofing (slab walls, 10’ area behind front step)? Should the concrete block be painted with drylock prior to insulating? Regarding floor insulation, should rigid foam be applied directly against the concrete or should a dimpled membrane be placed underneath it? Will condensation occur between the rigid foam and the concrete on the floor? Any thoughts would be greatly appreciated. Please see pictures of the basement floor plan and proposed wall assembly.
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由气候和房屋部件组织的一千个建筑细节的集合
答复
The dimpled membrane is a vapor barrier, but so is 2" of XPS, for all practical purposes. It's fine where you have it in the stackup.
MN code is pretty fussy about basement insulation stackups, but for retrofits most inspectors give a lot of leeway.
In your stackup it's worth using foil faced polyiso for the 2" interior side foam rather than EPS or XPS. XPS performance will deteriorate to that of EPS over it's lifecycle, and even with derating for temperature the polyiso will outperform it in this stackup.
虽然3英寸的闭孔绑在梁梁上有一些意义，但在墙上的顶部停止它泡沫（但密封它）并在螺帽墙的上半部分安装R15岩棉是一个更好的爆炸/巴克。该螺柱应紧紧靠近刚性墙体泡沫，没有间隙，并且高密度纤维被紧密到它。
An inch of EPS under the subfloor is fine, more is still worthwhile if you have the head room. The floor foam should extend all the way to the dimple mat, and under the bottom edge of the wall foam, especially if the wall foam is polyiso, which could wick moisture if resting on the slab.
谢谢你的回复达娜。关于凹陷的膜，您是否会对地下室的整个内部周边墙或仅进行外部防水的区域进行操作？为什么你建议箔面对eps或xps的polyiso？对于喷雾泡沫，您是否建议将一个1“层到空气密封件，然后摇滚Wooll在它的顶部没有涂层允许一些蒸汽渗透。并且EPS将直接在地板上，正确？
Thank you.
鉴于该地下室的水历史使用各地的凹坑垫。
Foil faced polyiso gives a higher R/inch, as well as an additional R1+ when facing a 3.5" empty 2x4 cavity. In the event of a fire (like polyurethane) it chars in place rather than melting into a puddle of burning liquid the way polystyrene (EPS & XPS) does.
For the spray polyurethane you'd need more than 1" for dew-point control on R15 rock wool in your climate but 2" is enough. As drawn the 3" spray foam covered the vertical face of the wall foam, and pushed the studwall further into the room, which is an unnecessary waste of space. With 2" of polyiso you have sufficient dew point control for R15 rock wool on the above grade section (that matters the most.)
您不需要或希望地板eps蒸发可渗透。落地泡沫和底层之间的6密耳聚乙烯蒸汽屏障保持地面水分，从发现它进入底层，而R4-ISH EPS足以保持夏季户外露点（至少最多）上方的底层时间），让它在夏天加入水分。EPS和板坯混凝土均良好地耐磨地铺设研磨水分，并且在蒸汽屏障的阻尼器接地侧功能很好。蒸汽屏障也降低了氡风险。
谢谢达娜，有意义。6米隆在地板EPS上面;这将在墙壁上徘徊，落后于墙壁上，涂上凹陷的膜6“左右？
听起来没错!
Keep the lapped poly sheeting between the dimple-mat & wall foam, not between the mat & foundation where bulk water coming through the foundation could potentially drain onto the top of the vapor barrier.
Andy,
看起来Dana已经回答了大多数问题。以下是一些观察结果：
1.在您的气候区（6区）中，大多数建筑规范要求地下室墙体绝缘材料具有R-15的最小值。在墙顶（冬季墙壁最冷的部分），你的绝缘层有点薄。不是一个大的交易，但你应该意识到的事情。
2.每股收益是有意义的——你aren't restricted to using polyiso.
3. You have designed a robust wall, which is good. You should know, however, that converting a basement with a history of water entry into finished living space is risky. Good luck.
在2×4壁中促进绝缘的薄膜 - 用于上述等级部分的2x4壁中的泡沫（任何类型）和R15贝蒂的性能（如响应＃1的推荐）超过Code-min连续R15的性能。
它还超过IRC第11章中的（无泡沫）的风险较高的2x6 / R19，这几乎肯定是您地下室的问题。
Dana,
Andy's drawing didn't indicate the presence of fibrous insulation between the studs. But I see that you recommended "high density fiber" in your Comment #1. That said, I wasn't sure whether Andy was going with the detail he had drawn up, or whether he would follow your recommendation.
安迪 - 看起来你已经在这里有很多好的建议。我会添加一个注意事项是，由于您似乎有一个块墙，我建议在最低点钻孔进入块芯，以排出水输出并进入排水场。https://www.mtidry.com/hyperspecs/interior-below-grade-cmu-wall-retrofit-moisture-control-detail用波纹排水垫表示这不带凹陷 - 要么会产生你需要的排水差距。控制腔和地板边缘溶液实际上由MASON / WIDELPROMER在明尼阿波利斯大约30年前设计，并在该地区干涸了很多地下室。Jeff Uhlferts Xeftbridge防水是在Ham Lake的上涨，多年来一直在安装这个系统。763-434-0579 MTI的详细信息显示系统的排水部分 - 遵循您在此处看到的绝缘建议。
Thank you all for the replies and helpful information. I would be happy to add more insulation, either doubling the foam thickness or adding batts from a couple feet below grade and up to the rim (Roxul, are these any less mold prone/better for a basement?). Back to Dana's original comment regarding MN code; I assume the inspectors here like poly on both sides of the stud wall which becomes a mold trap, which I'd obviously like to avoid. The inspector may suggest 6 mil poly on the wall insulation; this is exactly what Dana recommended under the subfloor. Would there be any problem with this? The EPS I can easily get has a very thin polymer coating on each side which I assume would be similar to a poly barrier.
For radon I will be sealing any cracks in the block wall; is it beneficial to apply drylock to the block also? Any moisture trapping issues?
关于墙面排水;现有的内部漏极铺扎已经有孔进入每个块的底部和延伸到瓦片的塑料管。我去年发现了这一点，当我不得不剪掉豌豆盆地并更换它。
Andy,
You can apply Drylock to the wall if you want -- but I have no idea whether the Drylock will help reduce radon. (Probably not.)
如果您最终将聚乙烯放入墙壁上以满足您的本地建筑检查员，则将其与混凝土块（块和刚性泡沫之间）更好，而不是墙壁的内侧。